Background: Mindfulness is considered a transdiagnostic process of change (Baer, 2007) which aids emotion regulation (Chambers, Gullone, & Allen, 2009). Clinically, mindfulness-based interventions can reduce depressive relapse (Kuyken et al., 2008) and increase wellbeing (Schroevers & Brandsma, 2010). However, it is not yet clear how mindfulness alters emotion processing (Davidson, 2010). This thesis examines the impact of both a brief lab-based mindfulness training, and longer term practice, on emotional response and related memory recall. Methods: We examined the impact of mindfulness on emotional response in both longterm meditators and matched controls. Participants underwent a brief training in adopting either experiential (state mindfulness) or evaluative self-focus whilst viewing a series of personality traits on a screen (Farb et al 2007). Images from the International Affective Picture System (Lang et al 1999) were then shown to investigate differences in emotional response. Self-reported arousal and valence ratings were collected, and skin conductance response (SCR) measured. We also investigated the impact of mindfulness on memory recall by administering a surprise recognition test. Results: People with more than 500 hours of meditation experience rated normatively negative stimuli as less unpleasant, and negative and positive stimuli as less arousing than controls. They also showed reduced SCR to positive stimuli. In addition, meditators scored higher on self-report measures tapping ‘non-reactivity’, ‘non-judging’ and ‘nonattachment’. No between condition differences in emotion processing were observed nor group differences on a memory task. Conclusion: Meditators showed measurable differences in emotional processing, both in subjective reports of their emotional experience and on a more implicit measure of physiological response. These data, while observational, are consistent with a state of calm equanimity in those with experience of meditation (Desbordes et al., 2014). The effects observed have clinical relevance, and may aid the understanding of the processes of change in mindfulness-based interventions.